HARQ Feedback Transmission in Unlicensed Spectrum

The patent applies preliminary action by configuring multiple candidate slots for HARQ feedback transmission in advance, but only activating them when channel conditions permit. The UE performs channel access operations to determine which configured slots can actually be used for transmission. This approach increases transmission opportunities and efficiency while managing interference through selective activation based on real-time channel conditions.

The patent applies dynamics by making HARQ feedback transmission adaptive to channel conditions. Instead of fixed transmission timing, the system dynamically selects from multiple configured slots based on channel availability detected through channel access operations. This dynamic adaptation allows the system to increase transmission opportunities when the channel is clear while avoiding contention and interference when the channel is congested, thereby improving efficiency without exacerbating harmful interference effects.

The patent applies preliminary action by performing channel access operations in advance of actual HARQ feedback transmission needs. The system determines channel availability and prepares transmission opportunities before data requires feedback, so that when feedback needs to be sent, the channel access decision is already made or can be quickly executed. This reduces the actual latency impact of channel access operations while maintaining reliability improvements.

The patent applies dynamics by adaptively adjusting channel access operation timing and duration based on channel conditions and traffic patterns. When channels are clear, simplified or faster channel access procedures are used, reducing time loss. When channels are congested, more thorough channel access operations are performed to ensure reliability. This dynamic adjustment balances reliability improvements with latency minimization based on real-time conditions.